Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Welcome to the forum. Do you have a specific CB500/4 in mind and if so, tell us about it, or just a general wish to buy any 500/4?
Its a mix of parts, looks like a K0 with a K1/2 rear mudguard and light